Projection device



March 18, 1941. c" E; ELLIQTT ETAL 2,235,701

PROJECTION DEVICE Filed April 20, 1958 3 ShGStS-ShGGt l C. E. ELLIOTTETI'AL March 18, 1941.

PROJECTION DEVICE Filed April 20, 1938 3 Sheets-She et 2 1721/6 a 3 0/;yak Z7 Z7560 Z Z" March 18, 1941- c. E. ELLIOTT ETALV PROJECTION DEVIG EFiled April 20 1938 3 Sheets-Sheet 3 a The above note toimmamg thebracke t h V sprockets "andfauitiltarykfilrnftransporting andPatentedMar. 18, 4 t

t if kppil icatio more particularly provided on a. rnovln transparentfilm, strip or ingas ascreen. l 1 pparatus r thi the like are rojectedon a suitable surface serv- 1932, have: disadvantages and drawbackswhich are 'javoided in the a structure disclosed herein.

sornelof the objeetsofthe present invention may be concisely stated asfollows:

housedjin separatehousings or casings, 1

Another object is cohcerned with a device of this type provided withnieans fonwithdrawin g the heated air rrom the lamp1;: casing in conjunctionwithladditional Ineansffor blowing. cold air.

upon the mqv nefb oie t o m at ano n Wher a,

i ex e dtbt e atray r Stillanother Obie tfrelatesto the provision ofmeans for increasing the length oii the filinand 1 mproperlyttensioriing thefihn, t v ob'ectrelates to the provision of a rrt e filterjfinhfr'ont of theprojectlon or condenser lensesfso sjtoahsorh the h t raysforthe purposel of conserving the filzn.

tures fnotf ye specificallyrnentioned will appear fromflthe r iowingotauedj description which is In renderedi with re ere ea to thedrawings.

35 ig.1 l'ifwsaltop view of theldevicep Fig. 2fshows a sideviewwwithcertain parts in section or broken away inorder o showinteriormechanisms; and

meta s a front iviwfort ilf(ant -Kuhn som g parts ojmittedandbtherpartsfin section "for the, I

purposeo ffacilitatilrig the des crlptipn. t

s1 necessary for; conveying indicatesa bas f carryin thefnotor m f nws nb 4 other detailswill presen y Qappear asithe descripon progresses:

intuit; iessyseriaiina; 203,038 i t aolainism; (01. 89 8): w ventionrelat s ftofprtscnaa deviceisfl The lamp housing concerned witha si nwProjection maci iinet wherein signs or characters n ebi t s c nc ne wita s gnl rbi *machine wherein thesalientjndividual partsare bj ects andother novel fea i The assernblyand coacltion of thesejand 1 l4 comprisesa suitably j shaped; vertically disposed sheet metal box carry? ing alid $1111 Fig; "1 the'lamp housing isshown withthelid l1open,exposlngthe projection lamp" [8. The lamp housingis heat lns ulatedye. g; it maybe lined with tsuitable heat resi'sting material such ass-heats ofasbestosjas indicated at I9, 20, 2|, and 22. The'lid IT mayalso beprovided with a diskor sheet ofheat-resisting material 23 secured by theears or projections 24-25) 26-211,; and 1 2B-'29.t"lfhis"sheet ispreferably positioned inspacedrelation tothetop of the V lid 11, leavingan internal 'space whichcom: municates gwiththe cutout 30 inthe sheet239* Thetop; of the lidv may be suitably perforated, as a indicated, soastoadmitthe air into*this space i and then; through the cutout 3|] intothe -interior of the housing L4, when the lid-is closed.

Inorder totakecare of determined ventilation of the lamp housing, thereis provided a fan frotor 3| (Figs. land 2) mounted on a shaft 32 whichis journalled in a bearing bracket" 33 Se cureduon the base ll,as,indicated at34-(Fig. *2). rThis shaft isoperated by the motor [2and is an extension of the motor shaft 35. The fan rotor 3l is placed infront of a suction casing 36which opens into the lamp housing at thebottom thereof, asindicated at 31 in Fig. 2. Accordingly; 1 when themotor rotates the shaft and with it the fan rotor shaft 32, the rotor 3|is actuated {and exhausts the.airtfrom thelarnp housing by away of theexhaust casing 36. "{Fresh air is sucked finto the lamp housingthroughthe perforations w on top of the lid 11 intothe spacedefined" by thetinsulatingwsheet fl downwardly into the lamp hou sing to-the bottomopening (Figl 2), where the air is expelledtby the action of the rotorfan 3|. The larnp I8 is thus continually cooled.

On the forward faceof the lamp housing is hirectlyin back of thefilmholder bracket l 5 "and provided a tubular ,extension 40 which extendscarries in its interior the usual condenserzlenses and .also',ifwdesired a filter for eliminating the heatfrays, Light fromthedampl8qis thus colf lectedanjdjis trained forwardlyona line substan- Ttiallyperpendicular to the larnphousing soajslto i I illuminate thetransparent film carrying the signs r to be projected or displayed.

T etprojection and focusingfapparatus is also: Y

{mounted on the,filni ,holder bracket member 151x as previouslymentioned. The bracket itself com-Q prises thetwo' uprights Mand fl,both show i the front view of Fig. 3, which rise; from the base H andare united in the center portion by across piece 43 which carries anopening B6 (Fig. l) in nalled the idler shaft 55 coupled directly to themotor I3 by means of the clutch coupling 56. The multiple holder bracketmember with all its projections and extensions may be made of anintegral casting, if desired.

The rods 505| extend through the projections 46 and 41 back to the lamphousing l4 and are mounted on the lamp housing by means of nuts, such asindicated in Fig. 1 at 58-59 and 605I., Screws, such as 62 (Fig. 2)maybe secured on the bracket projections .41 and 46 so asto fix theserods 50 and 5| in place and prevent inadvertent turning. The focusingassembly mounted on these rods 50 and 5| consists of the cross support63carrying the tubular holder 52. The cross support may be fixed at anyposition on the rods50 and 5| by means of the set screw 64, as shown inFig. 2. Inserted in the tubular holder 52 is the casing 65 which carriesthe usual focusing lenses. The rough focusing of the signs to beprojected (which are provided on the film or strip) may. therefore bemade bysliding the entire cross support 63 with its tubular holder 52and lens casing 65 with respect to the rest of the assembly, determiningthe rough distance of the focusing lenses from the film to be projected.The fine adjustment is then made by rotating the tubular casing 65soasto slide the focusing lenses to the desired position.

The film holder comprises the sprocket membars 61 and each having anupper and a lower sprocket, as shown in Fig. 2 at 60', and each mountedon a shaft, such as 10 and II, respectively. These shafts are.journalled at thetop in the cross piece 45 of the bracket support andextend downwardly through .the bracket projections "and 41, and eachcarries at its lower end a pinion,.as indicated at I2 and I3,respectively (see Fig. 3). The shaft 55 operated by the motor I2 throughthe gear means I3 and clutch coupling 56 is provided'with aslidablebushing '15 carrying a pinion, such as 16 and 11, at each end thereof.-This pinion bushing may be fixed on the shaft 55 either in the positionshown in Fig. 3 with drive pinion 'I'I engaging the driven pinion I3, orin the alternate position with the drive pinion I6 engaging the drivenpinion". Th bushing I5 may be secured on the shaft 55 in eitheralternate position by means of the set screw 80. Assuming now that themotor I2 operates, and that the drive is coupled with pinions I1 and I3in engagement, it will be clear that the shaft ll carrying the sprockets68 6 8 will be rotated as afdriven shaft and will carry the film in.theproperdire'ction determined by the rotation of the motor and by thedrive coupling as described. The-film 05 (the mounting and steadyingofwhich will presently be described) thus travels in front of the opening88 in the bracket |5- (Figs. 1 and 2); that is, it travels in front ofthe collected light emanating from the lamp housing and projectedthrough the opening 88. 1

In order to secure the proper operation of the film transport, there isprovided a film-steadying device 49 which is hingedly secured on theshaft 48, and this shaft in turn is journalled in the projections 90 and9| (Fig. 3) which extend forwardly from the bracket projections 48 and.41. This steadying device carries two idler rollers 92 and 93 providedwith suitable guide grooves which attach against thefilm 85 on thesprocket membars 51 and 68, as particularly indicated in Fig. 2. Aspring 94 is secured between the steadying device and the cross plate 43of the holder bracket so as to provide the requisite tension, holdingthe steadying device in the operating position with the rollers 92-93against the film, as shown in the drawings. If it is desired to changethe film, the steadying device 49 is tilted forward (to the left, asshown in Figs. 1 and 2), disengaging the film 85, whereupon the film islifted off the sprockets and removed. The opening 44 is-provided on thesteadying device in alignment with the light projection opening 05 inthe holder bracket, and the light emanating from the lamp I0 in the lamphousing I4 is thus trainedupon that film portion which happens to bepositioned at any time directly'in the line of the light rays. The imageof the signs on "the film then passes to the focusing lenses within thetubular casing 65 and is focused upon a suitable screen 'surface in awell known manner.

The film track casing I'6 may be made of an integral casting which, inthe embodiment shown, is roughly U-shaped when looking down upon theapparatus as in Fig. 1, with the forward ends I00 and IN of the twoopposite legs I02 and M0,, respectively,'rising from the base I04,extending inwardly and attached at I05 and I06, respectively, to theuprights of the holder bracket I5.

The film track casing isjsupported at the opposite'end by means ofbrackets such as |0| secured to the base II, as shown in Fig. 2. Thecasing is U-shaped in-cross section and may be covered by a lid I08, asis particularly apparent from Figs. 2 and 3, thus forming a tubularstructure which isdisposed circiunferentially around the lamp housingand secured to the holder bracket IS. The lid I08 ma be attached to theopen walls of the casing by means of thumb screws, such as indicated atI Oil-I I2,'inclusive.

The casing is provided with interior bosses, as shown inFig. 1 at H3,H4, H5 and 5, for taking the thumb screws I 09-1 I 2, inclusive. Thewall of the casing base I04 (Fig'.-}l-)', and also the side walls of theportions I02 and I03 are slightly recessed or cut out, as indicated inFig. 2 at III and H8, respectively, in order to permit properventilation of the film trackcasing when the lid I08 is put in place.

Within the film track casing are mounted spools, as indicated in Fig. 1at |20--|2|, inclusive,' for movably. supporting the film or strip 85,as shown. It will be noted that the film extends from the spool I22 byway of the spool I24 back to spool I23 which is'mounted adjacent.

spool I22. This arrangement accommodates a film of appreciablygreaterlength than was heretofore possible in such machines. The shaftof the spool |24 is supported in a. curved slot I30 (-Fig. 1) and isattached to a lever |3| which is suitably 'journalled at the bottomofthe casing at point I32. A tension spring I33 is anchored at one end tothe lever ISI, and is attached at the other end to the film trackcasing. The

lever III, and with it the spool I24 are therefore always biased inanticlockwise direction, puteon-g "caisson tween e spocls wing and thefunction of its individual parts, There is anotherfeature which is alsoconsida i sin ventilatijo of spool]? el l m imkv was s resk w ,Thes rous novel fe structure and arrangemeht of the film tracltcaseredofimportance in this disclosure, aiming at the ventilating m the filmcasing and direct; cooling of the'film atthe point where it is ex,

posed to the heat rays emanating from the pro- Jection lamp and alsocontemplating coolihg'of the motor. This provision comprises a secondrotor fancontainedin the casing I34 adjacent the rotor fan 3| butseparated from it. The, rotor blades of this fan are indicated indottedlines in'Fig. 2. l'lfhis rotords also mounted on the shaft}! whichtis anextension of the motor shaft 35 journalledat its rearendin the bracketwas e "thelfilmhousingr ;The air sucked in through the .yslotsl in themotor casing, andaround the motor 33. A funnel I35 is secured totherotor casing I34, rising frornit andis joined at its upper end n witha horizontally-extending, tapering funnel I36, the forwardend ofwhichtterminates' at [31 i at one side of the opening," inthe bracket I!ln back of the fllmjfll Cold air is sucked in, centrally from theoutside; land partly also through slots in the motor casing l2, bytherotor blades of the fan in the casing I34 and isforced throughtheffunnel sections I35 s and expelled at the funnel end lilandblowndirectlyin back i of the film section which at any moment 'hapi pens topass theprojectionopening of the device. 1 1 q Thefilmtherefore'iscooledat the pointwhere it 1 is exposed to the effect ofthe heat rays. The

stream oi cooling air thus blown against the, back of the film is, of:course, alsol'effective to ventilate effects cooling of the motorandthus preserves its life. The lift of i the? film i is 1 considerablyincreased and, of coursefthe hazards that may be connected with theoperation of such a deviceare to all practical intentsand purposeseliminated.

Other incidental advantages resultfrom this pro-v sision, which appearapparent and are, therefore,

notmentioned in detail. e e e l The circuit arrangementforrthe devicehas not been shown because it is well known to anyone who is experiencedin this art and informed about the intendedfunctions of the device asherein described. The circuitfof course, must include acurrent sourceanda suitable cord, preferably adjusting device is includedfor regulatingthe,

fwith a switch attached to it forcontrolling the connection anddisconnection of the current for,

the actuation of the motor and the lamp.u An

speed of the motor, which may be in the formjof a rheostat NI providedwithasuitableknob It.

The windingfof the rheostatrmay be connected in the circuit and when theknob II! is turned,

the resistance may be increasedor decreased, as

9 there isalso provided a setscrew I48 attached at the forward end tothe l I, as shown in rlgsrz and 3, and the front of the machinemaythecase may be. so asto adjust the speed ofthe particular operatingcondition. j i n Ordelhto P 1140!) the-machine correctly,

device, which isnecessary and desirable for any 70 i H thus raised orlowered as conditions demand.

saar i l is, whi h exte d d 3 aY ottte l r wbn nin s srs wn atw hespermit] rrqperw tilationlof the lamp-housing through the rotorfan 31 isone, while another ,jimpor'tant featureresides in the n ho i l 1, wTheoperation isaslfollowsz "-I fhe iilmcarrying the transparent signs maybe in the form I of an endless filmtstrip ort'bandn Ittis insertedfirst,

Itl i s understood, ofscourse, that-such set screws or equivalentdevices: may i .be provided at any other alternate or additional point,of; the ma andithis operation isgpreceded by removing the lid I"; fromthe film track casing and tilting 1 sprockets 61 and" for the receptionof the film. ,(I'he jfilm 85 is lthenthreaded over the spools in a ;thefilm track, as shown, and properly put on the sprockets whereupon thesteadying device ll is closed. The lid or cover ill may be replaced onthe filmcasing, The machine is then roughly trained toward the receivingsurface which may be any suitable surfaceor any suitable screen, l andthecurrent is'switched on. The speed of the steadying device 4! forwardso as to free the themotor is adjusted by the rheostat ill-Ill, and thesigns or, message then appear on the screen surface, the sequence of thecharacters or signs thus projectedcorresponding to their placing on thefilm strip. The apparatus is properly focused, at first roughly, byshifting the carrier 63 -52 on the rods BIL-|, and finally moving thefocusinglenses contained in the tube 65 within the tubular carrier 52until the mesysage properly appears on the screen surface withtherdeslred clarity and intensity.

Changes may be made within the scope and spirit of the appendedclaimswherein we have defined what is believed to be patentable and what isdesired to have protected byLetters Patent of theUnited States. v i

, We claim as our invention: i

1. In a sign projection machine of the class described, avertically-disposed lamp housing,

lens means mounted onthe side .of said housing,

a lamp in said housing forproducinglight to be trained to the outsidethereof through said lens means, a film carrying transparent signs, ahim tion of said film which isilluminated by the light emitted throughsaid lens means.

2, In a sign projection apparatus, a light source, a housing for saidsource, a lens holder mounted in one wall of said housing for formingalight beam, a film, guiding means for said fllm spaced away from saidlens holder, means for advancing said film through said guiding meansand across the path of said light beam, 0. motor,

means for connecting one end of the motor shaft to said film advancingmeans, a fan mounted on said shaft on the opposite side of the motorfrom said connecting means, a casing fol-said fan, and i an air conduitextending from said casing to a point just outside the light beam wherethe film guiding means is spaced away from the lens holder, said conduitincluding an end section making an angle with the axis of the beam and,adapted ;to direct a stream of air against the back of the film to coolthe same.

3. ,In a sign projection apparatus, a light source, a housing for saidsource, m'eans'including'said sourcepandfia lens system in one wall ofsaid housing for forming a light beam, a rum, means for moving said filmacross the path of said light beam, .3. motor'mounted alongside-saidhousing;,means for connecting one end of the motor shaft to saidfilm-:moving means, a fan mountedon the other end'of themotor shaft, 9.10 casing for said fan opening into said housing,

whereby the said fan circulates air through the housing,a-secondfanmounted on the motor shaftya ,casing' for the second fan, andan air conduit extending 'fromthe second casing to a V j CLYDE E.'LLIjoIT'r. FRANK SHAVEN.

